Water → 1,2,3,5-Tetrahydro-4,1-benzoxazepine

Participants

Reaction Conditions

Reaction Steps

To 1,5-dihydro-4,1-benzoxazepin-2-one (3.7 g, 22.7 mmol) in THF (75 mL) cooled with an ice bath was added lithium aluminum hydride (2.6 g, 68 mmole) portion wise. The reaction mixture was warmed to 80° C. and stirred for 2 hrs. This mixture was then cooled to rt and was treated with water (2.7 mL), 10% sodium hydroxide aqueous solution (2.7 mL) and water (8.1 mL). The resulting mixture was stirred for another 10 minutes before filtration through Celite. The Celite was washed with ethyl acetate and the organic solution was washed with brine (30 mL×2) before drying over MgSO4. Concentration of the filtrate and purification of the residue by silica gel column chromatography eluting with chloroform/methanol (99/1) yielded 1,2,3,5-tetrahydro-4,1-benzoxazepine 2-2 as a brown solid (1.65 g, 48% yield). MS: 150.0 (M+H)+; tR=1.02 min (method 1).

Provenance & Evidence